Meunier T, Vink I T, van Beveren L H Willems, Tielrooij K-J, Hanson R, Koppens F H L, Tranitz H P, Wegscheider W, Kouwenhoven L P, Vandersypen L M K
Kavli Institute of Nanoscience, Delft University of Technology, P.O. Box 5046, 2600 GA Delft, The Netherlands.
Phys Rev Lett. 2007 Mar 23;98(12):126601. doi: 10.1103/PhysRevLett.98.126601. Epub 2007 Mar 22.
We observe an experimental signature of the role of phonons in spin relaxation between triplet and singlet states in a two-electron quantum dot. Using both the external magnetic field and the electrostatic confinement potential, we change the singlet-triplet energy splitting from 1.3 meV to zero and observe that the spin relaxation time depends nonmonotonously on the energy splitting. A simple theoretical model is derived to capture the underlying physical mechanism. The present experiment confirms that spin-flip energy is dissipated in the phonon bath.
我们观察到了声子在双电子量子点中三重态和单重态之间自旋弛豫过程中作用的实验特征。利用外部磁场和静电约束势，我们将单重态 - 三重态能量分裂从1.3毫电子伏特改变到零，并观察到自旋弛豫时间非单调地依赖于能量分裂。我们推导了一个简单的理论模型来捕捉潜在的物理机制。目前的实验证实了自旋翻转能量在声子库中耗散。
